Since 9/11, the “Bush Doctrine” label has been applied to various aspects of administration policy, from the President’s initial “with us or against us” warning to state sponsors of terrorism, to his declared willingness to act preemptively (and, if need be, unilaterally) to head off the danger of covert WMD attack, to his assertion that final victory in the global war on terror depends on the spread of liberty across the Middle East and throughout the Islamic world. I will focus on this final usage, which is likely to prove the most lasting.

Is a campaign aimed at the political transformation of the “broader Middle East” essential to the defeat of terrorism? If so, how can it be carried forward to a successful conclusion at an acceptable cost? The first of these questions is easier to answer than the second.

I believe the administration’s assessment of the Islamist threat is fundamentally correct. In al Qaeda and its affiliates, we confront an enemy who aims to inflict as much pain on us and our allies as possible, thereby dividing the West, forcing a retraction of American power, and clearing the way for the overthrow of local “apostate” regimes and their absorption into a transnational caliphate. Having concocted quasi-theological justifications for their actions, the terrorists put no limit on the numbers they are willing to kill to achieve their goals; all that stands in their way is, for the moment, an apparent lack of means.

The menace we face may not be “existential,” in the same sense as the cold-war threat from the Soviet Union. Al Qaeda cannot rain down tens of thousands of nuclear warheads on American cities. But, with a few well-placed dirty bombs or vials of anthrax, it could impose terrible human and financial costs and radically alter, perhaps for a generation or more, the character of our open society and the extent of our integration into the global economy. The passage of time since 9/11, and the absence thus far of a follow-on attack on American soil, have caused some observers to lose sight of these dangers and even to argue that they have been grossly exaggerated. I know of no one involved in the conduct of the war on terror who shares this sense of complacency.

The ideology that motivates the jihadists has now metastasized and spread, so that it finds adherents even in free societies. But it sprang to life first in the diverse despotisms of the broader Middle East, and these are the sources from which it still feeds and which continue, either deliberately or indirectly, to sustain it. Even if it were possible to wave a wand and transform these societies overnight into functioning liberal democracies, the jihadist movement would likely live on, at least for a time. But unless and until progress is made in this direction, it seems certain to survive, and to thrive. The absence of liberty fuels frustration and extremism by cutting off avenues for more moderate forms of political expression, reinforcing social and economic stagnation, and feeding a sense of collective weakness, shame, and rage.

The other key elements of U.S. strategy—stronger homeland defenses and a relentless global offensive against Islamist terror networks—are necessary to keep the enemy off balance and reduce the risk of future attack; but they will not be sufficient, in themselves, to achieve a lasting peace. Jihadism cannot be defeated on the defensive, or even by cutting back its visible offshoots. It must be pulled up by the roots.

There are alternatives to a strategy that has transformation as its ultimate goal. If pressed, most liberal critics of the Bush Doctrine would say they agree with its ends but differ over means (more “soft” power and less “hard,” more multilateralism and less unilateralism). While the differences are in some respects overstated, there is a serious debate to be had here and a consensus to be hammered out, though controversies over Iraq have made this all but impossible for the moment.

More distinct are the options offered by advocates of what can only be called a policy of appeasement, on the one hand, and the self-described “realists,” on the other. The first group asserts that by leaving Iraq, cutting support for Israel, and perhaps withdrawing altogether from the Middle East, we may be able eventually to deprive the jihadists of their base of support. Despite the evident moral and strategic bankruptcy of these arguments, they have begun to gain ground recently in academic circles, where books “bravely” questioning our ties to Israel and “proving” that suicide terrorists are motivated solely by a desire to free their homes from occupation are currently the rage. Fortunately, such ideas seem unlikely for now to exert much influence on practical policy.

It is the “realists” who most stand to gain if American policy in Iraq comes to be seen as a costly failure. Such an outcome would be taken as proof that the pursuit of liberalization in the broader Middle East is a fool’s errand and that, instead of criticizing “friendly” local regimes and pressuring them to reform, we should be content to make common cause in wiping out the jihadists. What is needed, in this view, is a more effective and if need be a more ruthless version of the policy that existed before 9/11. The fact that this approach has already proved its ineffectiveness may not lessen its appeal, at least for a while.

In the long run, and whatever happens in Iraq, some variant of the Bush Doctrine will remain an essential part of overall U.S. strategy for defeating Islamist terrorism. The questions facing this administration as it enters its final quarter are more practical than theoretical. How to tailor the right mix of pressures and inducements to move “friendly” regimes toward meaningful reforms, and how to deal with openly hostile holdouts? How to minimize the inevitable risks of transition (the “one man, one vote, one time” problem)? How to institutionalize the “forward strategy of freedom” within the U.S. government and the Western alliance? And how to ensure continuing domestic political support for a goal that is both necessary and just?

AARON L. FRIEDBERG, professor of politics and international affairs at Princeton, served in the office of the Vice President from 2003 to 2005 as deputy assistant for national-security affairs and director of policy planning.